In the meat packing industry, whole boneless meat articles, such as hams, have been packed into lengths of tubular food casing and tied off at the ends to make discrete unitary packaged food articles. Such packaging techniques generally have involved slow and labor intensive operations. In such practice, a whole boneless meat article, a ham typically, is manually inserted loosely into a cut length of presoaked casing which has been pretied or clip-closed at one end. Insertion of the ham into the casing is accomplished manually or is assisted by means of one or another commercially available meat presses. In a subsequent pressure packing operation, the ham is tightly packed within the casing, simultaneously expelling entrapped air and shaping the ham. The operator may also "stick" the casing during the pressure packing operation, providing holes to further assist in expelling air from within the packed casing. The open end of the packed casing is then tied or clip-closed to complete the encased food article. Typical pressure packing techniques for boneless meat articles are shown and described in U.S. Pat. Nos. 3,115,733 to Tipper and 3,065,585 to Rumsey, Jr. Somewhat greater automation in the boneless whole meat article stuffing technology is shown and described in U.S. Pat. No. 3,919,739 to Kawai. Kawai utilizes a continuous band casing soaker in combination with a carriage means to continually put the open casing end into registration with a nozzle of a packing element. With the casing soaked and thus in place, a meat article is loosely packed into the temporarily held casing length. After a first clip is applied, the unclipped end of the packed casing is pulled tight around the meat article thereby shaping said meat article and expelling air entrapped within said packed casing. The unclipped end of the casing is then tied or clip-closed and the resulting encased meat article is severed from the casing supply feed length.
While the Kawai '739 apparatus represents an advance towards the goal of automatic ham stuffing, it does not provide a completely satisfactory technique. A significant disadvantage lies in the feeding of the casing being stuffed in a direction opposite the direction of progression of the articles being stuffed. Each stuffing action constitutes a sort of head on collision between the ham and the casing length into which it is to be packaged. Since, because of the apparatus design, there is no way to continually stuff the continuous casing band in a unidirectional mode with the direction of progression of the hams in process, this counterflow relationship between the casing band and the hams constitutes an inherent mechanical inefficiency. Another factor in the '739 patent technique which detracts from efficient packaging is that the hams are inserted into a loosely fitting casing which is subsequently drawn tight to shape the hams and to express air out of the package article.
Haettinger et al. in U.S. application Ser. No. 142,907, filed Apr. 23, 1980 and assigned to the same assignee as this application, discloses a method and apparatus for stuffing whole boneless meat articles, such as hams, into fibrous casing which avoid most of the inefficiencies and drawbacks of the prior art. As disclosed in Haettinger et al., a boneless meat article is arranged in a meat loading chamber with the meat fibers and fat cover, if any, properly oriented, and the chamber door is then closed and locked. The meat article is then compressed in the chamber and assumes a generally cylindrical shape. A two-stage piston first forces the article to be encased out of the chamber into a stuffing horn or tube and next forces the article through the stuffing horn into the preclipped end of the shirred casing supply. A second tie clip is then applied to close the casing.
The method and apparatus for inserting whole boneless meat articles, such as hams, into a shirred casing in accordance with Haettinger et al. are advantageous in that they allow for the continuous escape of air which otherwise tends to become entrapped during the insertion or stuffing process and further they permit gathering and clipping the open end of the stuffed casing while maintaining the encased product in a pressurized condition. In addition, the method and apparatus of Haettinger et al. contemplate a continuously repeating cycle wherein the deshirred end of a continuous succeeding preshirred casing is further gathered and clipped, and the completed stuffed product is severed from the succeeding casing.
Many whole, boneless meat articles are required to be packaged in food casing along with various types of preservatives, flavor-enhancers and other similar ingredients. These ingredients may be added to the meat article as a liquid or solid but in either case they usually readily dissolve in the natural juices or brine and the resulting liquidous product is generally referred to simply as "pickle". This pickle, after the meat article has been "pumped" and prepared for stuffing, will usually contain a small percentage of minute meat particles which tend to increase the viscosity of the solution. However, in most cases, the pickle flows easily amongst the pores of the meat article and will exude when the article is placed under compression in the meat loading chamber. Fortunately, most of the exuded pickle will be forced into the stuffing horn and eventually guided along with the meat product to the food casing. Consequently, the pickle loss will ordinarily not be significant enough to endanger the packaged meat article. However, in those instances where a large number of meat articles are to be packaged using the same stuffing apparatus, the exuded pickle tends to collect inside the apparatus and eventually escapes to the outer environment where it can cause troublesome cleaning and handling problems. Moreover, the pickle can corrode various metal parts, bearings and seals used in the apparatus and shorten their life.
In actual practice, most of the pickle that is lost during packaging escapes past the two-stage piston as it moves through the stuffing horn and collects behind the piston. During the next succeeding stroke, the piston is withdrawn and forces the pickle from inside the apparatus.
It is an important object of the present invention to provide an automatic, meat stuffing apparatus of the type described which aids in retaining most, if not all, of the pickle inside the packaged meat product.
Another object of the present invention is to provide an automatic stuffing apparatus of the type described which further permits whole, boneless meat articles to be effectively packaged and sealed along with all of the intended preservatives, flavor-enhancers and other ingredients which are necessary to maintain high quality even after prolonged periods of storage.
Another object of the present invention is to provide such an automatic stuffing apparatus which protects most metal parts, bearings and seals from contact with corrosive pickle that might otherwise exude from the meat articles to be packaged.
Another object of the present invention is to provide such an automatic stuffing apparatus which is relatively simple in construction and operation, which employs a minimum number of parts and which does not necessarily increase cost.